Grênivel Mota da Costa

Determination and Evaluation of the Metals and Metalloids in the Chapeu-de-couro (Echinodorus macrophyllus (Kunth) Micheli)

The Chapeu-de-couro (Echinodorus macrophyllus (Kunth) Micheli) is a native plant from Brazil, which has been mainly used in medicinal application being a potent antirheumatic and diuretic, in the production of soft drinks, and also in the ornamentation of aquariums. In this paper, the metals and metalloids for the leaves of chapeu-de-couro collected in the Paraguacu River from the city Cachoeira, Bahia State, Brazil, was determined and evaluated using multivariate analysis. The samples were digested using nitric acid and hydrogen peroxide and were analyzed using inductively coupled plasma mass spectrometry. The accuracy of the method was confirmed by analysis of a certified reference material of apple leaves, furnished by National Institute of Standard and Technology. The study involved 15 samples of the Paraguacu River. The results expressed as milligrams of element per kilogram of sample demonstrated that the concentration ranges varied: 1.39–5.27 for chromium, 44.85–165.39 for manganese, 0.55–0.84 for arsenic, 0.01–3.94 for antimony, and 0.18–0.31 for lead. The principal component analysis and hierarchical cluster analysis evidenced that the concentrations of the metals and metalloids varied according with the variations in the water of the Paraguacu.

Variações locais na riqueza florística em duas ecorregiões de caatinga

Resumo de caatinga do nordeste brasileiro ocorre principalmente sobre dois tipos de substrato principais: sobre solos derivados do embasamento cristalino pre-cambriano e sobre a cobertura arenosa das bacias sedimentares. Evidencias recentes tem demonstrado variacoes na dinâmica, estrutura e composicao floristica da caatinga desses dois macroambientes, o que fundamenta a necessidade de estudos com enfoque nas diferencas floristicas entre esses diferentes substratos. O presente estudo floristico das ecorregioes de caatinga, Depressao Sertaneja Meridional e Raso da Catarina, no municipio de Tucano, Bahia, e de especial interesse porque neste municipio ocorrem esses dois substratos em escala geografica local, permitindo ampliar o conhecimento sobre a heterogeneidade do Dominio da Caatinga. Neste trabalho e apresentado um inventario floristico de 14 localidades nestas duas ecorregioes da Caatinga. Em conjunto, as caatingas amostradas apresentaram uma alta riqueza floristica em comparacao com outras areas no nordeste do Brasil. Foram coletadas 450 especies, 288 generos e 82 familias. A maior riqueza em especies foi das Leguminosae, seguida por Euphorbiaceae. Nas localidades sobre substrato derivado do embasamento cristalino ocorreram 226 especies, enquanto nas de substrato arenoso ocorreram 284 especies. A proporcao de especies em comum entre esses dois tipos de substrato foi de apenas 13%. Diferencas em composicao floristica reforcam a hipotese de duas biotas distintas associadas aos dois principais tipos de substrato, que compoem a vegetacao da caatinga. Palavras-chave: floresta sazonalmente seca, Depressao Sertaneja Meridional, Raso da Catarina, semiarido brasileiro.

Flora das cangas da Serra dos Carajás, Pará, Brasil: Commelinaceae

This study provides detailed descriptions, illustrations, and morphological comments of the nine species of Commelinaceae registered for the cangas of Serra dos Carajas, Para state: Commelina benghalensis, C. erecta, C. obliqua, C. rufipes, Dichorisandra hexandra, D. villosula, Floscopa peruviana, Murdannia nudiflora, and Tripogandra diuretica.

Spatial distribution and associated flora of Alcantarea nahoumii, a vulnerable endemic species to rocky outcrops of the Serra da Jibóia, Bahia, Brazil

The objective of this study was to characterize the spatial distribution pattern at different altitude gradients as well as to investigate the flora associated with A. nahoumii, considered to be endemic and vulnerable. The study was carried out in Serra da Jibóia, Santa Teresinha, Bahia, Brazil. An inventory was conducted of young and adult A. nahoumii specimens along with taxonomic identification and quantification of the associated species. The cover percentage of A. nahoumii, rock slope, organic matter percentage and exposed rock percentage were calculated, as well as the following phytosociological parameters: absolute density, relative density, absolute frequency, relative frequency, and dominance of A. nahoumii. For the spatial distribution, three indices were tested (Morisita, McGuinnes and Payandech). Canonical correspondence analysis was also applied to test the association of the environmental variables with the species in the community. A total of 1,660 individuals were encountered and classified according to taxonomy in 17 families, 25 genera and 28 species. The spatial distribution pattern of the A. nahoumii population is aggregate. The results demonstrate that the population structure of A. nahoumii is stable, but events such as fires and extractive exploitation make the species vulnerable, along with the other species that inhabit the area.

Investigating the floral and reproductive biology of the endangered microendemic cactus Uebelmannia buiningii Donald (Minas Gerais, Brazil)

The Cactaceae are known to be amongst the most endangered plant families of the world due to reduction of their habitats and activities of collectors. As the species of the family are dependent on animals to perform cross pollination, and hence seed production, their population performance may be further negatively affected by interrupted biotic interactions. For efficient conservation of rare species, knowledge on reproductive biology and pollinators is of prime importance. In our study we focused on Uebelmannia buiningii Donald, a microendemic cactus from the Serra Negra State Park, Minas Gerais state, Brazil. During four field expeditions to three localities of the species between September 2012 and September 2013, we measured flowers, detected nectar-guides and osmophores and performed pollen viability tests. We studied the reproductive system of the species using manual self- and cross-pollination tests and observed pollinators. Our results revealed that the flowering period takes place during the dry season, between April and October, and that the diurnal flowers open between 7:00 a.m. and 5 p.m. The flowers are shortly tubular with yellow perianth-segments. We found neither nectar nor nectar-guides, and osmophores appeared as glands within the flower tube. Whereas pollen viability was 90.25%, manual cross-pollination tests have shown cross-pollination with gametophytic incompatibility. We observed two bee species visiting the flowers and acting as effective pollinators: Dialictus opacus and Plebeia sp. The combination of low reproductive activity with gametophytic incompatibility, together with the reduced number of individuals in a population and low number of populations, makes the endemic cactus U. buiningii a critically endangered species.

Cactus survey at the Floresta Nacional of Contendas do Sincorá, Bahia, Brazil

Summary: The Brazilian state of Bahia is home to 98 out of 260 species of the countrys native Cactaceae. The Floresta Nacional Contendas do Sincorá (FLONA Sincorá), in the Município de Contendas do Sincorá has vegetation, climate and temperatures typical of the Caatinga biome. The survey intended to increase the knowledge regarding the cacti of protected areas within the state of Bahia and was based on fieldwork carried out in April and July 2014 and February 2015, complemented by studies of herbarium material. The FLONA Sincorá harbours 11 genera and 14 species within its area: Arrojadoa penicillata (Gürke) Britton & Rose; Brasilicereus phaeacanthus (Gürke) Backeb; Brasiliopuntia brasiliensis (Willd.) A. Berger; Cereus jamacaru DC.; Espostoopsis dybowskii (Rol.-Goss.) Buxb; Hylocereus setaceus (Salm-Dyck) R. Bauer; Melocactus concinnus Buining & Brederoo; Pereskia aureiflora F. Ritter; Pereskia bahiensis Gürke; Pilosocereus catingicola (Gürke) Byles & G.D. Rowley ssp catingicola; Stephanocereus leucostele (Gürke) A. Berger; Tacinga inamoena (K. Schum.) N.P. Taylor & Stuppy; Tacinga funalis Britton & Rose; and Tacinga palmadora (Britton & Rose) N.P. Taylor & Stuppy. Of these, Espostoopsis dybowskii, Pereskia bahiensis and Stephanocereus leucostele are endemic to Bahia. The east Brazilian genus Tacinga was the largest, with three species. An identification key for all taxa, together with descriptions, illustrations, taxonomic and conservation and threat statements are presented.